Main features & Overview


3-phase "zero crossing" solid state relay for control of resistive and inductive loads.

Integrated device designed for industrial applications demanding control of high power levels and frequent switching, with loads up to 3 x 55A (AC51) at 400/480/600Vac.

Control is logic type (Vdc), signaled by LEDs. Each phase is controlled by means of semiconductors.

The constructive elements, special production process, and new, sturdy case, provide excellent reliability and continuity of service.

All versions are protected against overvoltages and against junction overtemperature, with signal LEDs and (optional) solid state alarm output.

The device is supplied complete with covers to protect against direct contacts (covers are removable for wiring).

Accessories available: heatsink, thermostats, fans, fuses and fuse holders.

The GZ models must be used in conjunction with an appropriate heatsink (Accessory).

Installation must precisely observe the warnings contained in the installation notes.


Zero-voltage switching.

Current range: 10A to 55A

  • 3-phase alternating current solid state relay
  • Zero crossing switching
  • 3-phase nominal current 3x10/25/40/55A
  • Nominal voltage up to 600VCArms
  • Control range: 5...32Vdc
  • Optoinsulation (input/output) 4000Vrms
  • Integrated overvoltage suppressor
  • Non-repetitive voltage up to 1200Vp
  • In Conformity with EN60947-4-3 and UL508


Gefran product range brochure
Power control
GZ datasheet
GZ Installation handbook


UL Certifications - UL - GTZ - GZ
CSA Certifications - GZ - GTZ
EU_Conformity declaration_GZ
UK Conformity declaration - GZ